Low Warning
1037 on Worcester Bosch Greenstar 8000 Life/Style

Your boiler has lost contact with its outdoor thermometer, so it is running at a pre-set steady temperature to keep your home warm while it ignores external weather changes.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Outside temp. sensor faulty - heating back-up operation active

What causes this fault?

This fault occurs when the boiler's control board can no longer detect a signal from the sensor located on the outside of your home. The most common reasons are that the external sensor has developed an electrical fault due to moisture ingress, or the thin wiring connecting it to the boiler has become damaged or disconnected.

This fault often comes to light during autumn or winter when the boiler first attempts to use weather data to adjust your heating for the colder weather.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

2916View →

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